iMac (Retina 5K, 27-inch, Late 2015)
4 GHz Intel Core i7
16 GB 1867 MHz DDR3
When trying to export a png using save for web at 7200x10800px, Illustrator automatically gives me a "new size" option that is significantly smaller than what I want to export. The largest I can export is 5461x8192, which is 75.8519% of the original size. I can go smaller with no problems, but when trying to go bigger it just tops out at 75.8519% for some reason. When I try exporting for screens, I just get an error message saying it can't export because of an unknown error.
Save for Web has a maximum dimension of 8192 px.
You can use Export As, check Use Artboards and 72 PPI and should get the result you want.
I'm using save for web
That did the trick, thanks! Now I know. Any insight as to why Save for Web has a max of 8192? That's a little odd in my opinion.
I guess when it was designed, screens of that size were not envisaged.
Since it is now a 'legacy' tool, this will likely never change.